What the tornado rating scale means in SC and how to be safe during hurricane season
As summertime thunderstorms start to pick up and hurricane season has begun as of June 1, it’s important to refresh on the various types of weather hazards.
From rain, hail, wind and flooding, there are a variety of factors to stay mindful of when bad weather strikes.
One of those factors that is increasingly dangerous is tornadoes. Big or small, these wind-powered forces can leave behind paths of destruction and can form in any storm, but how do meteorologists determine just how strong is a tornado?
The answer lies in the Enhanced Fujita Scale, a tool used by the National Weather Service to assess tornado intensity based on damage and estimated wind speeds.
The Enhanced Fujita Scale or more commonly referred to as the EF Scale, became operational in February 2007 and is used to assign a tornado a ‘rating’ based on estimated wind speeds and related damage.
Here is how this system works and what you should know in the event of hazardous weather.
History of the EF Scale
Originally named the Fujita scale, this system was developed in 1971 by Tetsuya Theodore Fujita, a Japanese-American meteorologist.
The system is designed to rate tornadoes and estimate wind speed based on the damage they cause based on a 0-5 rating system, which is still used today.
Why the name change?
The original Fujita Scale was a groundbreaking tool for its time, but its limitations, especially in how it estimated wind speeds, led to concerns about consistency and possible overestimation.
In 2001, the Texas Tech University Wind Science and Engineering Research Center, along with engineers, universities, private companies, government organizations and meteorologists from across the country, set out to improve the original system.
In 2007, the Enhanced Fujita system was launched, providing more reliable and accurate measures of wind speed and damage, including 28 damage indicators, ranging from minor damage to complete destruction.
Understanding the Scale
Here’s how today’s Enhanced Fujita Scale breaks down the wind speed for each tornado rating:
Tornado Rating | Wind Speed |
EF 0 | 65 to 85 mph |
EF 1 | 86 to 110 mph |
EF 2 | 111 to 135 mph |
EF 3 | 136 to 165 mph |
EF 4 | 166 to 200 mph |
EF 5 | 200+ mph |
It’s important to note that historical tornadoes rated under the original system are not reclassified.
For example, if a tornado rated before 2007 was an F5, the rating remains an F5, although its estimated wind speed may now be considered slightly lower than originally thought, according to the NWS.
Watches vs. Warnings for Tornadoes
Understanding the difference between tornado watches and warnings is one of the key ways to stay safe during inclement weather.
The NWS offers these distinctions and what to do during a tornado watch and a warning.
Tornado Watch: If a watch is issued, be prepared. Watches are issued if weather conditions make it possible for tornadoes to form in your area. The watch area is typically large, covering numerous counties or even states.
Tornado Warning: If a warning is issued, take action. Warnings mean a tornado has been sighted or indicated by weather radar. Seek shelter, avoid windows and move to an interior room on the lowest floor of a sturdy building. Warnings typically encompass a much smaller area (around the size of a city or small county) that may be impacted by an identified tornado.
Tornado Emergency: This means you should seek shelter immediately. A tornado emergency is the highest alert level from the NWS. It is issued when a violent tornado has touched down in the watch area. Once sheltered, be sure to monitor your local forecast for the latest updates.
Where to take shelter?
Hazardous weather can hit at any time, so understanding where the safest places to shelter, no matter where you are, is key.
No matter if you’re at home, on the road, at work or at school, be sure to identify the safest place to take shelter.
Here are the top recommendations from the NWS:
At home: The safest places include a basement, a central room on the lowest level of the house, bathroom, hallway or closet. Avoid any space with windows or heavy objects nearby. You can also cover your body with pillows for added protection.
Mobile homes: The NWS states that if you reside in a mobile home that was manufactured before 1976, you should seek shelter elsewhere, as these homes are vulnerable to high winds.
Vehicles: Any kind of vehicle can be interrupted by tornado winds. If you see a tornado, stop your vehicle and get out. For shelter, the NWS states that you should avoid any area with trees, lie down flat in a gully, ditch or low spot on the ground and protect your head with your arms. It is never recommended to outrun a tornado in a car.
Long-span buildings: Buildings such as a shopping mall, theater or gymnasium have roofs that are usually only structurally supported by the outside walls and can easily collapse. If you are in a long-span building during a tornado, stay away from windows and find the lowest level of the building. You can also shelter under a door frame or up against something that will support or deflect falling debris.
Public buildings: In buildings like offices, schools, hospitals and churches, move away from windows and glass doorways and shelter in the innermost part of the building on the lowest possible floor.
No matter where you seek shelter, always remember to protect your head and as much of your body as possible, as flying debris causes most deaths and injuries during a tornado, according to the NWS.
For more information on tornado safety, ratings and preparedness, visit the NWS tornado webpage.
This story was originally published June 2, 2025 at 8:08 AM with the headline "What the tornado rating scale means in SC and how to be safe during hurricane season."
